As the sport of bicycling has become more popular, transportation of bicycles for considerable distances on vehicle-mounted racks has become increasingly common, and the incidence of damage caused by impact of stones, insects and other objects against bicycles during such transportation at road speeds has become more widespread. The cost of bicycle frames and components has increased significantly in recent times, and the concern with prevention of damage to such frames and components has increased correspondingly. Prior art approaches to solution of those problems have been limited and have not been fully satisfactory.
One such approach involves fully enclosing the bicycle in a bag of canvas or similar material before mounting the bicycle on the carrier rack. While such enclosures are somewhat effective in deflecting objects from direct impact against the bicycle, or at least minimizing the damage from impact, they are cumbersome and time consuming to use, difficult to clean, and display a pronounced tendency to flap in the wind generated by vehicle motion, substantially increasing wind noise. In addition, the flapping of the material may damage or disturb the adjustment of delicate components of the bicycle.
Another approach has utilized a low profile deflector structure interconnected to the front of the bicycle carrier rack so that the deflector structure extends horizontally across the entire width of the carrier, but extends vertically through only a very small portion of the height of the bicycles to be mounted and transported thereon. This approach is very similar in concept to the known bug deflector devices intended to be mounted on the hood of an automobile in order to at least partially deflect bugs from the windshield of the automobile, as illustrated, by way of example, by U.S. Pat. No. 4,547,013 to McDaniel. While such structures are reasonably effective in deflecting bugs from vehicle windshields, they have not been similarly effective when used with bicycles.
A somewhat similar deflector device designed to be mounted on the roof of a vehicle is also known in the prior art, as illustrated by U.S. Pat. No. 4,206,942 to Nudo, et.al. Such devices generally comprise a rectangular shield mounted on the roof of a vehicle with the long axis of the rectangle across the roof and the short axis extending upward from the roof at an incline toward the rear of the vehicle. As viewed in the direction of air flow against the structures, such roof mounted deflectors are essentially larger versions of the hood mounted bug deflectors, and suffer essentially the same disadvantages in terms of effective shielding of a bicycle to be transported on the roof of the vehicle, as well as some additional disadvantages. The prior art deflectors do not normally extend to a sufficient height to fully shield the bicycle frame structure, and if extended to a sufficient height would create a severe aerodynamic drag highly detrimental to vehicle fuel efficiency. Because of the high wind load such deflectors typically require substantial support structures which leave insufficient space on the roof of most passenger vehicles to mount a bicycle and make the deflector structure heavy and cumbersome.
The prior art further includes a number of devices generally described as farings, designed to be mounted on a bicycle frame for protection of the rider and/or luggage while the bicycle is being ridden at normal pedaling speeds. Examples of such devices may be found in U.S. Pat. No. 4,655,497 to Mallett, U.S. Pat. No. 4,790,555 to Nobile, and U.S. Pat. No. 4,813,583 to Carpenter. While some faring-type devices provide some protection to the bicycle frame and components, any protection is a purely tangential result of their primary purpose and is incomplete at best. The structures of the faring-type devices are not designed to withstand wind loads imposed at vehicle highway speeds in any event.
Therefore, there remains an unfulfilled need for a shield device which effectively and efficiently protects a bicycle mounted on a carrier rack against impact by foreign objects during transportation at passenger vehicle highway speeds.